Lagoon is defined as a shallow body of water separated from the ocean or from larger bodies of water by a reef or other barrier.(noun)
An inlet off of the Pacific Ocean that is separated from the ocean by a coral reef is an example of a lagoon.
See lagoon in Webster's New World College Dictionary
Origin: < Fr lagune & It laguna < L lacuna: see lacuna
See lagoon in American Heritage Dictionary 4
Origin: French lagune
Origin: and Italian laguna
Origin: , both from Latin lacūna, pool, hollow, gap
Origin: , from lacus, lake.
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